Select Antipsychotics;Select Phenothiazines/Anticholinergics Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

These medicines may be prescribed together to prevent or treat side effects from your antipsychotic or phenothiazine medicine. In other situations, the combination may increase the likelihood of medicine side effects.

What might happen:

Muscle spasm or tremors due to the antipsychotic or phenothiazine medicine may get better with this combination. Side effects such as dizziness, dry mouth, sedation, blurred vision or constipation may start or get worse with the combination.

What you should do about this interaction:

If you experience increased constipation, drowsiness, dry mouth, dizziness, or blurred vision, contact your doctor. If you become confused, feel restless/agitated, or have difficulty urinating, let your doctor know right away. It may be necessary to discontinue or adjust the dose of one or both medicines.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

View Reference
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  • 15.Benztropine mesylate tablet US prescribing information. Bayshore Pharmaceuticals LLC December, 2013.
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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.